1. Field of the Invention
Embodiments of the present invention relate to vehicle seats.
2. Description of the Related Art
A vehicle seat generally has a cushion pad placed on a seat frame. The cushion pad is equipped with a main portion forming the seating surface for an occupant seated thereon, and side support portions provided on the sides of the main portion. The side support portions protrude from the main portion so as to support the sides of the body of the occupant.
The side support portions of the vehicle seat are of higher rigidity than the main portion, and are not subject to deformation with respect to external forces. Thus, the side support portions can effectively support the occupant, and suppress the discomfort due to side wires provided in the seat frame. However, when the side support portions exhibit generally high rigidity, the occupant cannot but experience their hardness when he touches them. Thus, it is desirable for the side support portions to have surfaces endowed with the same softness as that of the main portion. It is also desired that they have rigid cores.
According to Japanese Laid-Open Patent Application No. 2001-327357, previously formed insert material made of foam is inserted into a foaming mold. The insert material is set in position in the foaming mold. A foam stock solution is poured into the mold to cause foaming. As a result, a layer having relatively high rigidity is formed on a surface of the insert material. As a result, the surfaces of the side support portions are endowed with the same softness as that of the main portion. The cores exhibit rigidity at predetermined positions. The reason for forming a layer of relatively high rigidity on the surface of the insert material is to impregnate the surface portion of the insert material with the foam stock solution when pouring the foam stock solution into the mold, thus making the rigidity of that portion relatively high.
To insert the insert material into the foaming mold and to support it, it is necessary to provide a support member. As the support member is not a part of the final product, it is removed from the insert material after the completion of the molding. As a result of the removal of the support member, there remains a deficient portion at the corresponding area of the product. The deficient portion appears on the surface of the cushion pad, resulting in deterioration in the quality of the vehicle seat.
Therefore, there is need in the art for a vehicle seat involving no appearance of a deficient portion on the surface of the cushion pad resulting from the removal of the support member as mentioned above.